1.22 g of benzoic acid is dissolved in 100g of acetone and 100 g of benzene separately. Boiling point of the solution in acetone increases by 0.17$^{\large\circ}$C, while that in the benzene increases by 0.13$^{\large\circ}$C; kb for acetone and benzene is 1.7 K kg $mol^{–1}$ and 2.6 K kg $mol^{–1}$. Find molecular weight of benzoic acid in two cases and justify your answer.